New York, Oct 06: NASA has discovered 16 extrasolar planets in the central region of the Milky Way with its Hubble space telescope, hinting the possible existence of approximately six billion Jupiter-sized planets in the galaxy.
Five of the newly discovered bodies, the US space agency
said, represent a new extreme type of planet not found in any
nearby searches. Dubbed ultra-short-period planets, these
worlds whirl around their stars in less than one earth day.
"Discovering the very short-period planets was a big
surprise," said team leader Kailash Sahu of the Space
Telescope Science Institute, Baltimore.
"Our discovery also gives very strong evidence that
planets are as abundant in other parts of the galaxy as they
are in our solar neighbourhood."
The planet bonanza, NASA said, was uncovered during a
Hubble survey called the Sagittarius Window Eclipsing
Extrasolar Planet Search (SWEEPS).
Hubble looked farther than has ever successfully been
searched before for extrasolar planets. It peered at 180,000
stars in the crowded central bulge of milky way galaxy 26,000
light-years away. That is one-quarter the diameter of the
milky way`s spiral disk.
The tally is consistent with the number of planets expected
to be uncovered from such a distant survey, based on previous
exoplanet detections made in solar neighbourhood, NASA said.
Hubble`s narrow view covered a swath of sky no bigger in
angular size than two per cent of the moon`s area. When
extrapolated to the entire galaxy, the data provides strong
evidence for the existence of approximately six billion
Jupiter-sized planets in the Milky Way.